Hi Gang -
So I have a Pioneer SX-780. When I first got it a number of years ago it would power on, but no click. Did some research at the time and replaced the STK-0050 Packs (with what I'm sure were not the real thing, but impossible to find the real thing) and it's worked fine since then. Needless to say, I've had my fingers crossed that the packs wouldn't die.
The other day I got a pair of ADC 303AX speakers (in PERFECT condition, OMG) and hooked them up. Sounded perfect, but may have momentarily shorted + and - wires (the ADC 303AX have screw terminals that are too close together!) while powered on. Didn't think much of it, but went to put on the amp later and right channel was dead - no movement on the right watt meter at all. Swapped out amps and the speakers work, so it's not the inputs, speakers or connections. Left channel works fine, unit still powers on and gets that comforting "click."
I'm moderately skilled, and an eager student, but not an electrical engineer. I have a digital multimeter and, properly instructed, I'm comfortable testing and replacing components to a certain extent. With the end of the world upon us (kidding) i'm not really in the mindset to take this to someone to work on it, so I'm willing to dive in myself.
First - do we think it's likely one of the Power Packs? That's where my money is, but would love to get the group's thoughts and diagnostic recommendations. And if so, I don't know where I can source the real deal, might have to be content with the knock offs again. I've looked at the STK-0050 module replacement on ebay (https://www.ebay.com/itm/STK-0050-M...180725?hash=item1ccaf5a5f5:g:1FYAAOSwMfhadMhz) but while I'd be comfortable installing one that's put together, I'm not competent enough to assemble one myself with any degree of certainty.
And if not the power packs, what else should I be looking at. The fuses are all good - and if one were bad, I wouldn't have a functioning left channel, would I?
Anyway, pics attached. Would appreciate any and all thoughts. And remember, be gentle - I'm not experienced, but can follow directions! Thanks!
So I have a Pioneer SX-780. When I first got it a number of years ago it would power on, but no click. Did some research at the time and replaced the STK-0050 Packs (with what I'm sure were not the real thing, but impossible to find the real thing) and it's worked fine since then. Needless to say, I've had my fingers crossed that the packs wouldn't die.
The other day I got a pair of ADC 303AX speakers (in PERFECT condition, OMG) and hooked them up. Sounded perfect, but may have momentarily shorted + and - wires (the ADC 303AX have screw terminals that are too close together!) while powered on. Didn't think much of it, but went to put on the amp later and right channel was dead - no movement on the right watt meter at all. Swapped out amps and the speakers work, so it's not the inputs, speakers or connections. Left channel works fine, unit still powers on and gets that comforting "click."
I'm moderately skilled, and an eager student, but not an electrical engineer. I have a digital multimeter and, properly instructed, I'm comfortable testing and replacing components to a certain extent. With the end of the world upon us (kidding) i'm not really in the mindset to take this to someone to work on it, so I'm willing to dive in myself.
First - do we think it's likely one of the Power Packs? That's where my money is, but would love to get the group's thoughts and diagnostic recommendations. And if so, I don't know where I can source the real deal, might have to be content with the knock offs again. I've looked at the STK-0050 module replacement on ebay (https://www.ebay.com/itm/STK-0050-M...180725?hash=item1ccaf5a5f5:g:1FYAAOSwMfhadMhz) but while I'd be comfortable installing one that's put together, I'm not competent enough to assemble one myself with any degree of certainty.
And if not the power packs, what else should I be looking at. The fuses are all good - and if one were bad, I wouldn't have a functioning left channel, would I?
Anyway, pics attached. Would appreciate any and all thoughts. And remember, be gentle - I'm not experienced, but can follow directions! Thanks!
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